Water-heater



N. HUBBARD.

WATER HEATER.

APPLlcAloN FILEDJUNE30.1917.

Patented Aug. 17, 1920.

MMMNMMM N. HUBBHD. WATERVHEATER. APPLICATION FILED IUNE 30. |917.

I,349,571`. Patented Augn 17, 1920.

2 SHEETS-SHEET 2.

:mum/bici MMM La lt/ l UNITED STATES PATENT OFFICE.

NORMAN HUBBARD, 0F ELIZABETH, NEW JERSEY, ASSIi'-NOR 0F ONE-HALF TOPEREZ M. STEWART, OF NEW YCRK, N. Y.

WATER-HEATER.

Specification of Letters Iatent.

Patented Aug. 17, 1920.

To all 'whom t may concern:

Be it known that I, NORMAN HUBBARD, a citizen of the United States,residing at Elizabeth, county of Union, and State of New Jersey, haveinvented certain new and useful Improvements in VVater-Heaters, of whichthe following is a speciiication.

My invention relates 'in general to water heaters, that is to say,apparatus for raising-the temperature of water, whether for the purposeof simple heating or for the generation of steam. More specifically, theinvention concerns water heaters of the type in which a gas flame isemployed as the heating medium.

Apparatus of this class may be employed for example to produce hot waterfor ordinary household purposes, or for producinlg hot Water for use inheating systems. t will, however, be understood that the apparatusitself which forms the subject matter of the present invention, might,if desired,

be employed for heating other liquids. Among the objects of thelnvention, I may mention the pur ose to provide a water heater of high eciency and of simple design or construction. ther objects are forrexample to produce a water heater of convenient size and formforhousehold u se and one which can be readily connected with the gasand water supply systems already present. The invention is illustratedby way of example in the accompanying drawing, in which,

Figure `1 is a central vertical section throu h a water heating unit,constructed accor ing to my invention,

Fig. 2 is a horizontal section thereof taken on the line II--II of Fig.1, and

Fi 3 isda similar section taken on 'the line III-III of Fig. 1.

The embodiment herein shown is designed so as to be readily connectedwith the gas and water pipes, involving but one gas 1nlet and singlewater inlet and outlet connections. As clearly shown inF ig. 1,--theapparatus is grouped within a cylindrical housing -10 of, for example,metal tubing or sheet metal, lined with Suitable heat insulatingmaterial 11, as for example asbestos packing. The housing cylinder ismounted between heads 12 and 13, 'thewater inlet pipe 14 extendingaxially through the head 12 while the water outlet pipe 15 extendsaxially out through the head'13. It will be understood that the unitcomprises a water system and a gas system so associated that duringpassage oi the water through the un1t, it is exposed to the hightemperature of burning gas, the low temperature water entering throughpipe 14 and the heated water passing out through the pipe 1 5. The watersystem comprises, in addition to the inlet and outlet pipes 14 and 15,lower and upper headers 16 and 17 with which the pipes 14 and 15 aresuitably connected and between which are disposed in the presentinstance, three Water tubes 18 of for example, drawn sheet metal.Concentrically disposed within each of the tubes 18 is a fire tube 19,which extends across the water space in each header for the purpose ofmaintaining the water within each of the tubes 18 in the form of anannular body. Tube 19 in each instance is threaded at either end, oneend being screwed into tapped hole in bottom of lower header 16; uponthefree end of tube 19 is screwed a bushing 20 having a conical outersurface fitting within a similarly formed orifice in the .top of upperheaderl. The ends of tubes 18 are in each instance fitted into conicalorifices in the top and bottom of lower and upper headers respectively.

The headers 16 and 17, together with the tubes 18 and 19, are firmlysecured in their assembled position by turning the conical bushin s 20in the proper direction, both ends 0I fire tubes 19 being threaded inthe same direction, (see Fig. 1), so that the two headers are given atendency to move in opposite directions on the fire tubes, against theresistance offered bythe engagement of the conical ends of the watertubes yin their respective seats. In this way a iirm water tightengagement of the various joints is secured.

Referring to Figs. 1 and 2, it will be clearly seen that the three tubes18 are distributed .uniformly around the main axis of the unit and thatthe header 16 which receives the incoming water from the single axialinlet pipe, distributes the Water to the three rising tubes from whichthe three bodiesl of heated water are again united in the header 17prior to discharge through the The gas system of the unit is somewhat.

similarly subdivided from the common source so as to provide a pluralityof individual gas flames or burners for the introduction of heat intothe water sub-divisions. The single gas inlet is represented at the pipe21 as connecting with an air-mixing element 22 of well knownconstruction, from which the combustible mixture of the air and gaspasses through pipe 23 into two sets of burners, each of which issub-divided into individual burners for the respective watersub-divisions. burners receives its mixture of gas and air through therising pipe 24 from which it is distributed through the annular burners25 disposed above the header 16 surrounding respectively the three watertubes 18 so as to apply heat'to the outer surface of the annular columnin each of said tubes. The

\ lower set'of burners likewise receive their mixture of gas and airfrom pipe 23 and are distributed uniformly around the main axis of theunit, one burner or outlet 26 being provided in axial positionimmediately beneath each of the inner tubes 19. The flames from burners26 are directed upwardly into the inner tubes 19 where they encounter ineach case a helical deflector 27 which throws the flame outwardlyagainst the inner wall oftube 19. These helical deflectors 27 areconstructed for example in the form of castings or twisted sheet metalstrips which fit snugly within the tubes 19 and are provided at the topwith lateral ears 28 whichjrest upon the top of the bushings 20 tomaintain them in proper position with their lower ends a short distanceabove the bottom of the fire tubes. The deflectors not only spread thevame centrifugally outward against the inner wall of tubes 19, but theylikewise prolong the travel of the fiame through the tubes and form heatconductors which transfer heat into the tubes 19 so that a highlyefficient delivery of the heat units contained in the fuel is madepossible.

The products of combustion from the inner and outer burners aredischarged through the common outlet 29. In order to retard the exit ofheated gases from the outside burners 25, a metal baffle plate ordiaphragm 30 is disposed in the upper portion of the unit and extends towithin a short distance of the inner wall of the cylindrical The upperset ofv housing, so that an eflicient heating chamber is maintainedwithin the space inclosed by the housing.

With the construction above described, it will be clear that not only isthe water sub-divided into a plurality of individual bodies for thereception of heat, but these individual bodies are in the form ofannular columns to which the heat is applied at both the interior andexterior surfaces. The proportionate surface area to the total volumemay in this way be made very great and suitable proportioning ofdiameters of the tubes 18 and 19, together with the proper selection ofthe number and length of subdivisions employed, will adapt the device tomeet a wide range of requirements as to rapidity and capacity ofheating.

The provision of conical seats for the connection of the tubes with theheaders, while being shown in the preferred form, is to be understood asmerely illustrative of a construction in which the orifices and the endsof the tubes are tapered or flared in one direction or the other, sothat relative movement of the two headers toward or away from eachother, as the case may be, will have the effect of bringing the adjacentsurfaces of the tubes and headers into firm water-tight contact.

I claim l. A water heater comprising in com bination, a water inletbelow and a water outlet above, means for sub-dividing the water on itsway from inlet to outlet into a plurality of upright annular columns,means for locally producing a heating iiame within the lower portion ofthe space inclosed by each of said annular columns, and an annularburner surrounding the lower portion of each annular column foi` locallyproducing a ring of heating fiame in proximity to the outer surfacethereof.

2. A water heater comprising in combination a water inlet below and awater outlet above, means for sub-dividing the water on its way frominlet to outlet into a plurality of upright annular columns, an axiallydisposed burner below each of said annular columns for delivering alocal flame into the lower portion of the interior space inclosed byeach of said annular columns of water and a circumferentially disposedannular burner at a somewhat higher elevation surrounding the lowerportion of each of said annular columns of water for delivering a localring of flame in proximity to the outer surface of each of said annularcolumns of water.

3. A water heater comprising in combination, horizontally disposed upperand lower t headers, upright water tubes operatively connecting thesame, fire tubes passing through said water tubes and headers, anaxially disposed burner below each of said re tubes for delivering alocal llame into the lower portion thereof, and a circumferentiallydisposed annular burner above the lower header and surrounding eachwater tube for delivering a local upwardly directed ring of flame inproximity thereto.

4. A water heater comprising in combination an upright fire tube, meansfor maintaining a supply of water around said lire tube, an axiallydisposed burner for delivering a local upwardly directed flame into thelower portion of said fire tube, and a helical deflector disposed withinsaid fire tube and terminating at a short distance above the lower endof the re tube.

NORMAN HUBBARD.

